Nahid Shahabadi - Department of Inorganic Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran and Medical Biology Research Center (MBRC) Kermanshah University of Medical Sciences,Kermanshah, Iran
Saba zendehcheshm - Department of Inorganic Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran

The interaction of ketotifen fumarate with Human serum albumin (HSA) at physiological pH has been investigated by absorption, emissionand molecular modeling. Spectrophotometric studies of the interaction of ketotifen with DNA have shown that it can binds to HSA and the HSA binding constant(Kb) is 1.313 ×104 M-1. The Ksv values in our study, decreased with the increase in temperature, which indicated that the quenching process was static quenching process. The negative value of ΔG revealed that the interaction process was spontaneous. The positive ΔH and ΔS values indicated that hydrophobic forces play main roles in the binding of ketotifen to protein. The observation confirmed that the binding of ketotifen to HSA is located within domain III, Sudlow’s site 2. This result corroborates with molecular modeling simulations. The docked structure shows that the drug is located within the binding pocket of site 2 (subdomain IIIA) hydrophobic zone of HSA and is surrounded by amino acid residues such as Lys‐436, Ser435, Lys‐439, Gly‐434, His‐440, Cys‐434,Val-433.

ketotifen fumarate, static quench, hydrophobicity, Human serum albumin